.box {
  width: 100vw;
  height: 1000vh;
  position: relative;
}
.box .container {
  position: absolute;
  top: 50px;
  left: 100px;
  width: 500px;
  height: 50%;
  background-color: aqua;
}
.box .container .price {
  background-color: #ddd;
  position: absolute;
  top: 100px;
  left: 100px;
  width: 100px;
  height: 100px;
}
.back {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #ddd;
  border-radius: 50%;
  display: none;
  z-index: 100;
}
